Worksheet on magnetic energy contains various types of questions.
The important information will help us to the answer the questions given below.
Electromagnet: A temporary magnet, developed within a magnetic substance by electrical energy.
Magnet: A piece of iron having a special power to attract other iron bodies towards it.
Demagnetization: Removal of the magnetic properties of a magnet.
Magnetization: Method of developing magnetic properties in a magnetic substance.
Magnetic substance: The substances, which are attracted by a magnet and can be magnetized by magnetic induction.
Magnetic pole: The two opposite ends of a magnet, which have the strongest power of attraction.
I. Write true or false of the following:
(i) Very high temperature makes a magnet weak.
(ii) Magnetic energy flows through a copper wire.
(iii) A magnet, wrapped with a plastic sheet cannot attract a piece of iron any more.
(iv) South pole of a magnet always attracts the south pole of another magnet.
(v) When a piece of iron is kept near a very strong magnet it becomes hot.
II. Fill in the blanks:
(i) The property of ________ helps us to distinguish between a pair of magnets and a pair of iron bars.
(ii) South pole of a bar magnet repel the ________ pole of another magnet.
(iii) An iron bar placed near a magnet behaves like a ________.
(iv) North pole of a magnet attracts ________ pole of another magnet.
(v) The door of a refrigerator get tightly closed by ________.
III. Answer the following questions:
(i) If a pin head is held near the mid-point of a magnet bar, what will happen?
(ii) If a piece of wood is kept near a magnet bar, what will happen?
(iii) How can you separate iron filings from sand?
(iv) What will happen if the North pole of a magnet is held near the South pole of another magnet?
(v) Ron have two magnets and a iron bar. How can you identify the iron bar out of it?
(vi) What happens when a piece of iron is held near a bar magnet?
(vii) How can we transform an iron bar into a magnet bar?
(viii) How can we transform a magnet bar into an ordinary iron bar?
(ix) Suppose if we keep a magnet in fire for sometime what will happen?
(x) What will happen to an electromagnet if you disconnect the power supply?